The increasing need for communications networks and capabilities in outlying and geographically diverse locations has created greater demand for cellular systems. Many new carriers providing the infrastructure for such systems have focused their resources on building as many terrestrial cell stations as possible to expand their respective areas of coverage and consequently generate more revenue.
However, the buildout rate for the terrestrial cell stations is typically slow and expensive, especially in mountainous or otherwise difficult to access areas. In addition, in some these areas, a carrier's return on investment may not provide the incentive necessary for the carrier to build the necessary cell stations, thereby leaving these areas with either limited or no cellular service at all. Further, many areas having a sufficient number of cellular communications base transceiving stations to handle calls during both off-peak and peak times cannot adequately handle large volumes of calls during sporting events or other short-term special events that temporarily attract large crowds.
In response to the above, airborne cellular systems have been proposed in which a cellular repeater mounted in an airplane, flying a predetermined flight pattern over a geographic area requiring cellular coverage, links calls from cellular phones within the covered geographic area to a terrestrial base station. Because the airplane is capable of traversing geographic limitations and takes the place of the cell stations, such a system overcomes the above-mentioned limitations of conventional terrestrial cellular systems.
Despite its many advantages, an airborne cellular system presents design and implementation considerations not present in the design and implementation of conventional terrestrial cellular systems. For example, an airborne system typically includes a single airplane carrying a cellular repeater. Therefore, when the plane encounters adverse weather conditions, its flight pattern, and therefore the coverage area of the repeater, must be altered. Currently proposed airborne systems utilize a high-altitude airplane that is capable of flying above adverse weather conditions. However, as such an airplane requires specially-trained pilots, special maintenance and longer missions, therefore, associated system costs are increased. Clearly a need exists for solutions to the aforementioned problems.